Discharge system
If the system has lost all refrigerant due to a leak, follow the steps below.
Empty the system.
Fill the system with refrigerant: approximately 480 to 520 g.
Check for leaks.
Empty the system.
Eliminate leaks.
Attention! The filter-drier assembly is replaced when the air conditioner is not running. The desiccant used in these installations is quickly saturated with water from the air atmosphere. When installing the dehumidifier, prepare all the necessary tools and materials for a quick replacement in order to keep the system open to the air as little as possible.
Replace receiver dryer.
Empty and prime the system.
Small system discharge
If the system has not lost all of its refrigerant charge, locate and repair any refrigerant leaks. If necessary, pressurize the system to make it easier to find leaks by adding refrigerant. If possible, repair the refrigerant leak without emptying the system; in this case, use the appropriate technique when recharging the system.
Piping and connections
Loops in the pipes or sharp bends in the air conditioning hoses will drastically reduce the efficiency of the system. In this case, the pressure in the elements of the system increases sharply during the operation of the air conditioner. Particular attention must be paid to the reliability of fastening of all system connections. Dirt and moisture can get into the system when it is repaired in the process of replacing lines or elements of the system. The following precautions must be taken into account. Before disconnecting any fittings of the air conditioning system, the system must be completely emptied. Even with a completely empty system, the disconnection of the system fittings must be done with extreme care. If pressure remains in the system when the fittings are disconnected, the pressure must be released very slowly.
Changing the shape of pipelines by re-bending them is not allowed. It is allowed to use pipelines of original bending during their installation. For flexible hoses, there is a rule for the maximum bending radius: it must be at least 10 hose diameters. A smaller bend radius reduces the fluidity of the refrigerant. Flexible hoses of the air conditioning system must not run closer than 80 mm from the engine exhaust manifold. It is a good rule of thumb to inspect the flexible hoses of the system annually: their condition and the condition of the seals.
In the presence of seals such as O-rings: they must not be reused.
Checking the noise level of the air conditioner
It is necessary to know the reasons for the appearance of extraneous noise during the operation of the compressor. These reasons may be: weather, vehicle speed, movement in gear or coasting, engine thermal condition and other reasons.
The noise that appears during the operation of the air conditioner can sometimes be misleading. For example: A worn bearing or loose connecting rod noise can be caused by loose bolts, nuts, mounting brackets, or a worn magnetic clutch. Check drive belt tension (power steering, generator). Incorrect drive belt tension can cause a distracting noise when the compressor is turned on and reduced or no noise when the compressor is turned off. Drive belts are very sensitive to speed. At different engine speeds and depending on the tension of the belts, the belts can make a sound that is easily confused with the noise of mechanical compressor failures.
Adjustment
Select a quiet area for testing. Repeat the same type of situation many times when checking. Turn the air conditioner on and off several times to clearly distinguish the noise produced by the air conditioner. For simulating harsh environments (high pressure), limit the air flow through the condenser. Install a measuring manifold to create an outlet pressure not exceeding 2070 kPa.
Tighten all compressor mounting bolts, clutch mounting bolts, tension the compressor drive belt. Check the condition of the winding of the compressor electromagnetic clutch (lack of rotation or mobility).
Check the condition of the A/C hoses for friction or entanglement that may cause additional noise.
Check refrigerant charge.
Check again for noise from step 1.
If the noise persists, loosen the compressor mounting bolts and retighten them. Repeat step 1.
If the noise still persists, replace the compressor and repeat the test from step 1.